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CVE-2018-11236: GNU Glibc: Buffer overflow

CVE-2018-11236 is rated critical with a CVSS v3.0 base score of 9.8 and affects GNU Glibc, along with 8 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

stdlib/canonicalize.c in the GNU C Library (aka glibc or libc6) 2.27 and earlier, when processing very long pathname arguments to the realpath function, could encounter an integer overflow on 32-bit architectures, leading to a stack-based buffer overflow and, potentially, arbitrary code execution.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-190: Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

CWE-787: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

Affected products

  • GNU Glibc: up to and including 2.27
  • Red Hat Virtualization Host: 4.0
  • Red Hat Enterprise Linux Desktop: 7.0
  • Red Hat Enterprise Linux Server: 7.0
  • Red Hat Enterprise Linux Workstation: 7.0
  • Oracle Communications Session Border Controller: 8.0.0; 8.1.0; 8.2.0
  • Oracle Enterprise Communications Broker: 3.0.0; 3.1.0
  • Netapp Data Ontap Edge: all versions listed by NVD
  • Netapp Element Software Management: all versions listed by NVD

References